Increasing Prevalence of Antimicrobial Resistance Among Uropathogens Causing Acute Uncomplicated Cystitis in Women

TLDR

Let's craft. Background sentence: "Guidelines for treating acute uncomplicated cystitis in women rely on predictable antimicrobial susceptibility patterns of the causative agents." That's fine. Purpose sentence: "This study assessed the prevalence and trends of antimicrobial resistance among uropathogens causing acute uncomplicated cystitis in a large cohort of women." Good. Mechanism sentence: "A cross‑sectional survey of 4,342 urine isolates collected every three months from 1992 to 1996 in a health‑maintenance organization was performed." Good.

Abstract

ContextGuidelines for the management of acute uncomplicated cystitis in women that recommend empirical therapy in properly selected patients rely on the predictability of the agents causing cystitis and knowledge of their antimicrobial susceptibility patterns.ObjectiveTo assess the prevalence of and trends in antimicrobial resistance among uropathogens causing well-defined episodes of acute uncomplicated cystitis in a large population of women.DesignCross-sectional survey of antimicrobial susceptibilities of urine isolates collected during a 5-year period (January, May, and September 1992-1996).SettingHealth maintenance organization.PatientsWomen aged 18 to 50 years with an outpatient diagnosis of acute cystitis.Main Outcome MeasuresProportion of uropathogens demonstrating in vitro resistance to selected antimicrobials; trends in resistance over the 5-year study period.ResultsEscherichia coli and Staphylococcus saprophyticus were the most common uropathogens, accounting for 90% of the 4342 urine isolates studied. The prevalence of resistance among E coli and all isolates combined was more than 20% for ampicillin, cephalothin, and sulfamethoxazole in each year studied. The prevalence of resistance to trimethoprim and trimethoprim-sulfamethoxazole rose from more than 9% in 1992 to more than 18% in 1996 among E coli, and from 8% to 16% among all isolates combined. There was a statistically significant increasing linear trend in the prevalence of resistance from 1992 to 1996 amongE coli and all isolates combined to ampicillin (P<.002), and to cephalothin, trimethoprim, and trimethoprim-sulfamethoxazole (P<.001). In contrast, the prevalence of resistance to nitrofurantoin, gentamicin, and ciprofloxacin hydrochloride was 0% to 2% among E coli and less than 10% among all isolates combined, and did not change significantly during the 5-year period.ConclusionsWhile the prevalence of resistance to trimethoprim-sulfamethoxazole, ampicillin, and cephalothin increased significantly among uropathogens causing acute cystitis, resistance to nitrofurantoin and ciprofloxacin remained infrequent. These in vitro susceptibility patterns should be considered along with other factors, such as efficacy, cost, and cost-effectiveness in selecting empirical therapy for acute uncomplicated cystitis in women.